This invention relates to microscope drapes that form a disposable sterile covering for surgical microscopes, and more particularly to a novel microscope drape with a one-piece main cover and one or more sleeve portions that have a reinforced joint with the main cover.
Microscopes used for surgery are generally permanent fixtures in an operating room, and often have an articulated cantilever support arrangement to facilitate movement of the microscope over an operating zone. Such microscopes can include, in addition to ocular portions, one or more viewing tubes or laser arms that project away from the microscope housing. Since an operating room usually requires sterile conditions for all furnishings, it is common practice to cover the microscope and any associated support structure with a disposable sterile covering or drape.
The microscope drape generally remains on the microscope during the performance of a surgical operation and ideally does not interfere with any of the functions of the microscope. Microscope drapes are normally replaced just prior to an operation to ensure that the microscope covering is substantially sterile during an operation.
In order to effectively cover the microscope, along with any projecting viewing tubes or laser articulating arms and associated microscope support structure, it is usually necessary to form the microscope drape with one or more sleeve-like portions to accommodate the projecting viewing tubes. Because it is not feasible to custom fit a drape to a microscope, the drape is normally made oversize and secured at predetermined locations on the microscope structure to take up undesirable slack. Since the microscope and its support structure have an irregular periphery, the securement of the drape around the microscope structure usually causes stretching or tension at some portions of the drape, especially at the joint between the main cover portion and the sleeve-like extensions.
U.S. Pat. Nos. 3,528,720; 3,698,791, and 4,266,663 show microscope drapes with sleeve-like extensions that are formed to extend from a main cover portion of the drape. The sleeve-like extensions as well as the main cover are a continuous integral structure. However, the main cover portion is made in at least two pieces that are seamed or heat welded at their edges. During installation of the drape upon a microscope, the sleeve-like extension and the main cover portion are secured to corresponding microscope structures. If the points of securement of the drape are in close proximity to the joint between the sleeve-like extension and the main cover portion, there is likelihood of a tension buildup at the joint or seams that can cause the drape material to stretch, rip or rupture.
A further problem with microscope drapes of the type described is that the material used to form the drape usually must have a minimum lateral width equivalent to the width of the main cover portion and the lateral extension of each sleeve from the main cover portion. Since the lateral width of the main cover portion is often substantially less than the overall lateral distance between the ends of the sleeve-like extensions, a substantial amount of material must be sheared or otherwise removed from the stock material used to form the drape. If the removed material cannot be used there is considerable waste.
It is thus desirable to provide a microscope drape with a one-piece seamless main cover portion and sleeve-like extensions that have a reinforced joint between the sleeve and the main cover portion.